<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        *{
            margin: 0;padding: 0;
        }
        .box{
            width: 100%;
            height: 600px;
            background: #ffff00;
            margin-top: 50px;
            /* overflow: auto; */
            /* float: left; */
            /* position: absolute; */
            display: inline-block;
        }
        .wrap{
            width: 100%;
            height: 300px;
            background: #008000;
            margin-top: 150px;
        }
    </style>
</head>
<body>
    <div class="box">
        <div class="wrap"></div>
    </div>
</body>
</html>